Feasibility and incremental benefit of puffed-cheek 18F-FDG PET/CT on oral cancer patients.

PURPOSE: The complexity of small oral cavity and intimate apposition of the oral cavity mucosal surfaces make CT identification of obvious masses difficult. Puffed-cheek CT improves the evaluation of oral cavity lesions. We used the puffed-cheek maneuver with 18F-FDG PET/CT scans to determine the feasibility and accuracy in clinical practice and to identify any benefits. PATIENTS AND METHODS: Twenty-two patients with oral cancer were included. They were instructed to perform the puffed-cheek maneuver after a conventional 18F-FDG PET/CT scan. Two physicians reviewed the puffed-cheek and conventional 18F-FDG PET/CT images and achieved consensus about the cancer extent, location, and dental artifacts before classifying and grading the oral cancers. Dichotomous results of localized or extended cancer and artifact grading scores from the puffed-cheek and conventional 18F-FDG PET/CT methods were compared using McNemar test and the Wilcoxon signed-rank test. P < 0.05 was considered significant. RESULTS: The puffed-cheek maneuver with 18F-FDG PET/CT was practical and had incremental benefits. The conventional 18F-FDG PET/CT classified 12 patients correctly as having localized or extended cancer, and the puffed-cheek 18F-FDG PET/CT classified 21 patients correctly. Puffed-cheek 18F-FDG PET/CT found a synchronous skip cancer and provided detailed cancer delineation. This method might reduce the effects of dental artifacts without undesirable muscular FDG uptake. CONCLUSIONS: Puffed-cheek PET/CT is feasible in the current clinical setting and can improve the delineation of oral cancer extent and location, with a potential benefit of reducing dental artifacts.

The properties of sintered calcium phosphate with [Ca]/[P] = 1.50.

In order to obtain the properties of the sintered as-dried calcium phosphate with [Ca]/[P] = 1.50, the characteristics of sintered pellets have been investigated using X-ray diffraction (XRD), inductively coupled plasma-mass spectrometry (ICP-MS), Fourier-transform infrared (FT-IR) spectra, Vickers hardness indentation and scanning electron microscopy (SEM). When the pellet samples were sintered between 700 °C and 1200 °C for 4 h, the hydroxyapatite (Ca(10)(PO(4))(6)(OH)(2), HA) still maintained the major phase, accompanied with the rhenanite (NaCaPO(4)) as the secondary phase and ß-tricalcium phosphate (ß-Ca(3)(PO(4))(2), ß-TCP) as the minor phases. In addition, the HA partially transformed to α-tricalcium phosphate (α-Ca(3)(PO(4))(2), α-TCP) and tetracalcium phosphate (Ca(4)(PO4)(2)O, TTCP), when the pellet samples were sintered at 1300 °C and 1400 °C, respectively, for 4 h. The maximum density and Vickers Hardness (HV) of sintered pellet samples were 2.85 g/cm3 (90.18% theoretical density (T.D.)) and 407, which appeared at 1200 °C and 900 °C, respectively.

Automated framework for digital radiation dose index reporting from CT dose reports.

OBJECTIVE: Radiation exposure from CT studies has increased over the past 30 years in the United States and now constitutes approximately 50% of the radiation dose index administered in the health care setting. Tracking CT dose index (CTDI) is cumbersome because it relies on a manufacturer-generated screen capture, which contains the estimated dose index exposure for the patient. The radiation dose index information is not digital but, rather, is "burned" into the image (i.e., not in numeric form, not as part of the image header or elsewhere associated with the study), making it difficult to automatically share these data with other information systems. The purpose of the dose index reporting application (DIRA) we developed for CT is to extract the radiation dose index information from the CTDI reports to eventually perform automated quality control, promote radiation safety awareness, and provide a longitudinal record of patient-specific health care-related radiation exposure. MATERIALS AND METHODS: A random selection of 518 CTDI reports were processed by the DIRA and the dose index information was extracted. CTDI reports using a standard DICOM C-STORE to the DIRA allow an automated process to compile radiation dose index and patient information in a Web-based framework using a structured query language (SQL) database. RESULTS: Our initial tests showed that the DIRA accurately extracted dose index information from 518 of 518 CTDI reports (100%). Because the extracted CTDI descriptor-dose-length product-is based on standard CTDI measurements obtained using fixed-size cylindric polymethylmethacrylate phantoms, preliminary studies have been performed to correct for patient size by applying correction factors derived from CTDI measurements using a range of phantom sizes from 6 to 32 cm in diameter. Our system provides a way to automatically track CTDI on existing CT scanners and does not rely on the DICOM SR Dose Index Report standard, which is available on only the newest CT scanners. CONCLUSION: A modular and vendor-independent DIRA system can be integrated with any existing CT scanner. This system greatly facilitates digital dose index reporting and makes it possible to provide a longitudinal record of the health care radiation exposure estimate in an individual patient's health record.

Langerhans cell histiocytosis of the lung with probably skeletal involvement.

Langerhans cell histiocytosis is characterized by abnormal accumulations of large mononuclear cells forming granulomas in various organs mainly in the lung, bone, or skin. Adult pulmonary Langerhans cell histiocytosis is rare and almost always associated with cigarette smoking; combination with lung and bone simultaneous involvement is even rare. We present a 41 years old male smoker who was diagnosed with pulmonary Langerhans cell histiocytosis by a lung biopsy and manifestations at high resolution computed tomography of the lung. Later technetium-99m methyl diphosphonate bone scintigraphy showed multiple abnormal tracer accumulation of the radiotracer in the skull and a singular focus in a rib.

Hashimoto thyroiditis and Takayasu aortitis: visualization of the thyroid gland and ring appearance of the mediastinum on F-18-FDG PET.

A woman with Hashimoto thyroiditis, treated with levothyroxine for 4 years, complained of chest pain that radiated to the neck and had progressively worsened for 2 months. CT of the chest showed circumferential thickening of the ascending aorta and aortic arch, compatible with Takayasu arteritis. She underwent F-18 FDG PET imaging, which revealed an abnormal thyroid gland and a ring-like appearance of the mediastinum.

Active bleeding in hematoma of the abdominal rectus muscle shown by Tc-99m red blood cell scintigraphy: compared with CT.

A patient with cirrhosis of the liver complicated with left rectus muscle hematoma following paracentesis underwent consecutive noncontrast CT images and a novel Tc-99m red blood cell (RBC) bleeding scan. Six liters of clear yellow fluid were withdrawn. Progressive enlargement of a left rectus muscle hematoma was diagnosed by 3 consecutive CT scans and confirmed by a Tc-99m RBC bleeding scan. Although consecutive CT scans showed progressive enlargement of the hematoma, the radionuclide study showed an active bleeding site.

Photon-deficient Mass on FDG-PET Scan in Renal Cell Carcinoma: A Case Report.

F-18 Fluorodeoxyglucose Positron Emission Tomography imaging (F-18 FDG PET) detects malignancies depending on the uptake profile of glycolysis of tumors; however, the role of FDG PET is limited in the evaluation of primary renal malignancy because of low FDG uptake by renal cell carcinoma and also because normal urinary excretion of FDG seen in the images. A patient with renal cell carcinoma whose FDG PET imaging study incidentally shows a photon-deficient mass in the upper pole of the right kidney is present here. The diagnosis is also validated by the histopathological findings of tumor necrosis, hemorrhage, and scars.

Life-long follow-up in congenitally corrected transposition.

A male patient with congenitally corrected transposition, with no associated cardiac malformations, was diagnosed in childhood and followed until his death at age 28. He underwent two cardiac gated single photon emission computed tomographies over a two year period, which demonstrated progression of ischaemia and reduction of systolic function. The findings suggest that, when the systemic ventricle is perfused by the morphologically right coronary artery, there may be inadequate perfusion to supply any subsequent extensive hypertrophy.

2-Deoxy-2-[F-18]fluoro-D-glucose positron emission tomography illustrates two visceral tumors in a post kidney transplant patient with multiple cutaneous malignancies.

The success of renal transplantation brings with it the dilemma of managing patients with complications from lifelong immunosuppressive therapy. Immunosuppressed transplant recipients are a special population with significantly increased risk for development of skin cancers. Because malignant tumors are increasing as demonstrated on 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) positron emission tomography (PET) image, we report the unusual coincidence of multiple cutaneous cancers and two visceral malignancies 20 years after renal transplantation. The malignancies include basal cell and squamous cell carcinomas and malignant fibrous histiocytoma. FDG-PET images show, in this case, visceral masses with increased metabolism: one in the left upper lung and one in the abdomen, corresponding to individual mass lesions observed on computed tomography (CT) images of the chest and abdomen. A fine-needle biopsy of the nodule of the left upper lung lobe yielded a diagnosis of a sarcoma. The mass lesion of the abdomen had caused bowel obstruction, requiring exploratory laparotomy; histopathological findings from the resected mass from the abdomen confirmed the diagnosis malignant fibrous histiocytoma. This long-term immune suppressed transplant recipient developed viscerally located malignant lesions demonstrated by FDG-PET imaging and three types of cutaneous malignancies (skin cancers).

F-18 FDG PET demonstrates crossed cerebellar diaschisis 20 years after stroke.

Stroke produces an area of focal damage and distant areas of reduced blood blow and metabolism termed diaschisis. Tc-99m ECD and HMPAO brain SPECT have demonstrated crossed cerebellar diaschisis (CCD) in patients with cerebral cortical infarct. SPECT findings reflect abnormal cerebral blood flow. CCD as shown on F-18 FDG PET reflects abnormal reflects glucose metabolism. We present the case of a patient with laryngeal cancer who also had a stroke in the left cerebral hemisphere involving the territory of the middle cerebral artery 20 years ago. This patient underwent PET, including the head and neck. A current brain F-18 FDG PET exhibited hypometabolism in the contralateral cerebellum (CCD) as well as hypometabolism of the primary insult in the left cerebral hemisphere. These findings reflect partial impairment or diminished glucose metabolism in the primary insult to the cerebrum and contralateral cerebellum. In addition, this patient illustrates that on PET imaging, CCD could be demonstrated 20 years after a stroke.

Gastric-emptying scintigraphy of type III hiatal hernia: a case report.

We present the case of a 76-y-old man with mixed (type III) paraesophageal hernia confirmed by endoscopy and CT of the chest who underwent a radionuclide gastric-emptying study that showed accumulation of the radiotracer in the herniated stomach and esophagus in the thorax and accelerated gastric emptying. A scintigraphic gastric-emptying study may be an option for noninvasively demonstrating gastroesophageal accumulation of tracer in patients with hiatal hernia.